The present invention relates to a pusher and switch assembly for electronic watches.
In the use of electronic watches, particularly multi-function digital watches, it is necessary to have switches which enable the user of the watch to, for example, select the desired display function or to illuminate the display. A pusher for actuating a switch within an electronic watch is disclosed in U.S. Pat. No. 3,783,607 to Feurer, which issued Jan. 8, 1974.
Other prior art patents of interest include U.S. Pat. No. 3,874,162 to Boxberger et al, issued Apr. 1, 1975; U.S. Pat. No. 3,757,512 to Zellweger et al, issued Sept. 11, 1973; and U.S. Pat. No. 3,621,649 to Vulcan et al, issued Nov. 23, 1971. These prior art patents are merely typical of the art showing devices to control the watch functions.
However, in contrast to the prior art, the present invention provides a pusher and switch device having a simple, robust and relatively inexpensive one-piece pusher stem structure, and a single stamped or blanked return spring affixed or held inside the watchcase under spring pressure. The pusher can readily be assembled during mass production and dismantled for cleaning and overhaul without using special tools since the assembly does not require press fittings. The spring is contoured such that the tension against the shaft, case wall and watch module provides excellent electrical connection of the shaft to the grounded case. Due to the structure of the shaft and spring assembly, the sealing grommet can have a more massive body, permitting large compression which improves the sealing qualities. And the small diameter of the pusher shank or shaft permits thinner case profile.